Sun Dawu, chairman of Dawu Agriculture Group, was detained in November with 19 family members and business aides following a land dispute between his company and a state-owned farm.
The People’s Court of Gaobeidian said Mr Sun was also fined 3.1 million yuan ($480,000 or £345,800).
Dawu group said other defendants received sentences ranging from one to 12 years, according to The Associated Press. The company was also directed to refund the investment that was raised improperly, totalling 1 billion yuan ($155 million), it said.
Mr Sun has been convicted on charges including obstructing public affairs, gathering people to attack state organs, illegal mining and illegally taking public deposits, among others.
His lawyers said the trial happened in secret and the secrecy “violated legal guidelines and did not protect the defendant’s litigation rights,” according to AFP.
But defence lawyers had earlier said that while the trial was open to the public, the number of spectators was capped due to coronavirus restrictions. They had said only one spectator from the family of each defendant and 10 from the company were allowed, AP reported.
Mr Sun was earlier arrested in 2003 and charged with “illegal fundraising.” His release came after an outpouring of public support for him.
He founded the Dawu group in the 1980s, and it employs thousands of people now. While authorities initially hailed his success, The Guardian reported that he provided support to human rights lawyers and dissidents.
Chinese entrepreneur Wang Yingguo, who is also close to Mr Sun, told VOA in November that if there was a financial dispute with another company, the matter should have been handled as a civil case.
He said: “Now, his company has been taken over by the government. The story has become more than the company itself.”
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